close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2113559

код для вставки
April12,1938.
WABENDRQTH
STEAM GENERATOR
2,113,559
Aprnìl 12., 1938.
w. ABENDROTH
2,1 13,559
STEAM GENERATOR
Filed July 15, 1956
2 Sheets-Sheer. 2
` . .mv
,
ß
Cl
í
3
@_
Pf
/7
SUPER #wrm
È
@www
W5www
A»
„W
m#
.,
W
„M
r
@2N2_/Mf
.Z
„,
P.
@i
W
w
,
ä
m mWm
r//.\|J
4
2.113.559
Patented Apr. 12, 1938
um'rlanv STATES
PA'I‘EISITv orrlcl-z¥
>`2,113,559
`
'
STEAM GENERATOR
Wilhelm'Abendroth, Berlin-Charlottenburg, Ger
many, assigner to Siemens-Schuckertwerke
Aktiengesellschaft; Berlin-Siemensstadt,r Ger
many, a corporation of Germany
Application July 15, 1936, Serial No. 90,636
In’Germany July 18, 1935
5 Claims. (Cl. 122-418)
My invention relates to a steam generator in
which the operating medium flows on its way
from the point yat which the liquid is fed to the
point at .which the steam is drawn oil for in
5 dustrial or other purposes only once over a heat
ing surface formed of tubes and in which only
so much liquid is supplied in the unit of time in
the state of equilibrium of operation as is neces
sary to generate the steam required by the con
l0 sumer. 'I'his type of steam generator which I
shall designate in the annexed claims as being
of the "forced single ñow» tubular` type” has as
is well known only a relatively small storing ca
pacity so that a governing apparatus is required
16 which rapidly acts on the supply of fuel and
operating medium, if the production of steaml is
to be effected in accordance with considerably
fluctuating demands of steam.
The drawback of the above-mentioned steam
330 generator may be overcome according to the in
vention by inserting a drum or the like partly
iilled with liquid operating medium in the path
of ilow of the operating medium in such a man
ner that in the state of equilibrium of operation
£5 dry saturated steam enters the liquid or a coil
open at one of its ends and located in the liquid.
whereas the steam collecting in the space above
the liquid- is superheated in the heating surface
part connected in series with the drum and that
a0 upon fluctuations of the liquid level in the drum
the normal level is reestablished by correspond
ingly varying the ratio of the quantity of operat
ing medium fed into the heating surface part
connnected in series with the drum to the quan
35 tity of heat supplied to the heating surface part.
In this manner the druminserted in the path
of ñow brings about a state of equilibrium in the
case of a fluctuating demand of steam, i. e., the
liquid contained therein evaporates upon a sud
40 'den increase oi' demand of steam or in the case
"of a decrease of demand of steam the drum acts
as accumulator. This drum forms acomponent
of the generator and is as above mentioned in
operative connection with the governing appa
45 ratus of the generator insofar as the liquid level
in the drum is brought again to the normal level
after decreasing or increasing the quantity of
. liquid in the drum by varying the state of the
steam ñowing from the generator to the drum in
50 accordance with the liquid level in the drum.
The adjustment of the liquid level in the drum
to the normal level coincides Vin-other words, con
sequently, with the regulation of the boiler. The
regulation of the steam generator according to
ß the invention is eiïected in a very simple manner.
The supply of the feed water is controlled, on >the
one hand, according'to the invention in accord
ance with the quantity of steam issuing from the
drum and, on the other hand, in accordance with
the liquid level in the drum, the governing appa
ratus being so arranged that both control im
pulses may act without interference on the mem
ber controlling the supply of feed water. The
control is eñected in- such a manner that van ¿.
increase of demand of steam from the drum as
well -as'a lowering of the liquid level in the drum
results in an increased supply of the feed water
or that conversely in the case of a decreased
demand of steam or of an increased liquid con
tent the supply of leed water decreases. In this 15
case, the supply of fuel takesplace in accordancel
with the pressure prevailing at` the point of the
boiler at which steam is drawn oir for general l
use. The supply of the fuel may also be controlled
lin accordance with the liquid level in the drum N 0
and with the quantity of steam issuing from
the latterI whereas the supply of the operating
medium may be controlled in accordance with
the pressure prevailing at the point of the boiler
at which steam is drawn off for general use.
_
In the accompanying drawings an embodiment
of my invention is shown in diagrammatic form.
In these drawings Fig. 1 represents a sectional
elevation of the steam generator and Fig. 2 rep
25
resents diagrammatically an` arrangement for 30
neutralizing the effect of ñow resistance intro
duced by the equalizer vessel.
As will be seen from Fig. 1 the path of flow of
the operating medium may be traced by follow
ing the reference numerals l to 23. The essen 35
tial component of the boiler shown is the drum
I4 which is. filled with liquid operating medium
in the state of equilibrium of operation up to a
certain normal level. The governing apparatus
consists. substantially of a quantity measuring
device 24 which measures the quantity of steam
issuing from the drum I4 and oi a iioat> 25 which
responds to the variation of the liquid level in the
drum I4. The governing apparatus for the sup
ply of the fuel may have any conventional form,
such as for instance illustrated in the U. S, Pat
ent No. 1,904,443 to Hans Gleichmann. The con
trol of fuel supply may be effected accordingly in
the present case by the control piston 30, spring
controlled in cylinder 3|, the latter being con 50
nected to the consumer’s main 23, so that the
piston has normally the tendency to close the4
fuel valve 32 when the pressure in thekmain 23
drops, and to open ity when the pressure rises.
As long as the system is in the state of equi
-2
_
9,118,559
libniumof operation thedruml4isn1ledupto will be corrected which was the cause of the dis
its'normal level with liquid and the boiler is
tired or fed in such a manner that the steam
supplied from the pipe I3 and entering the drum
is‘iust dry saturated. Bincevdry saturated steam
is also taken from the drum the liquid content
of the drum remains, consequently, always un
changed during this operating condition. A dis
turbance of this equilibrium of operation may
10 either occur by variation from any cause of the
ratio of the quantity of water fed into the boiler to
the fuelgsupplied. or by the occurrence of' a more
or less sudden change in the demand of steam. If
the ratioof the quantity of water fed into the
15 boiler to the quantity of. fuel supplied varies dry
saturated steam will no longer pass through the
pipe Il into the drum I4, but either more or less
superheated or wet steam.
'
,
turbance of the. operating equilibrium; however,
if the supply of fuel is to be corrected this correc
tion will be brought about in accordance with
the pressure of the steam supplied.
Of particular importance is the behavior of the
boiler and the operation of the governing appara
tus in. case the boiler is operated in the state of
equilibrium and the consumption of steam iluc
tuates. If the demand of steam suddenly in 10
creases the following takes place: At the first
moment the increased demand of steam causes
-a decrease in pressure at the point of the boiler
at which the 'steam is drawn off. The supply
of fuel which is controlled in accordance with
that operating factor increases. With decreasing
pressure auxiliary steam is developed lfrom the
liquid contained in the drum. This pressure de
In case superheated steam flows through
crease in drum I4 is of course not so extensive
the pipe Il into the drum I4, the water content and
sudden as to cause a violent swelling up of the
of the latter decreases. If the pipe I3, however, liquid, but such decrease is rather gradual and 20
Supplies wet steam the liquid content will gradu
progressive during the period of unbalance, so
ally increase. In the ñrst case the float 2i causes that merely the evaporation of liquid becomes
the valve 2B located in the feed pipe Ito open greater than its supply to the drum. The liquid
a further amount, whereas in the other case the level in they drum therefore drops so that the feed
25
float 25 eii'ects a further movement of they valve
28 will be opened further by the float 25.
towards the closed position. The above-de .valve
increased quantity of steam issuing from the
scribed regulation effected by the float is further 'I’he
supported _by a regulation effected in the same drum causes through the quantity measuring de-'
30 manner by a steam quantity impulse. That is ' vice 24 also a further opening of the valve 2G.
the~boiler is not only supplied .with 30
to say, if superheated steam is introduced into Consequently,
an increased amount of fuel but also with an in
the drum I4 instead of saturated steam, the drum creased
amount of feedwater so that it will be
supplies an increased amount of steam, whereas able to supply
also a greater amount of steam.
if wet steam instead of dry saturated steam is
35 supplied to the drum the latter delivers a smaller Notwithstanding this fact the state of equilibrium
is not yet attained. Theliquid level in the drum 35
amount of steam. As will be apparent from the
governing apparatus shown an increase in the must nrst be again adjusted to its normal value
and the supply of fuel and of water must be
supply of steam causes the valve 26 to open fur
brought into relationship with each other in such
ther, whereas in the case of a smaller supply of a manner that upon the attainment of the normal
40 steam the valve 26 is caused to move further to
liquid level in the drum the latter supplies again (D
wardsy the closed position. As will be seen, the through
the pipe I3 dry saturated steam. 'I‘he
two impulses act, consequently, in the same sense further regulation
is now eil'ected in exactly the
on the regulating member 26 so that the normal
same manner as in the above-described case in
liquid level in the drum I4 is quickly reestablished. which the ratio of the feed water to the quantity
45
It hes in the nature of this regulation that in
of fuel has been disturbed. Upon a sudden de 45
the case of any disturbance of the proper ratio crease
in the demand of steam the regulating op
of the quantity of the feed water to the quantity erations
are carried out in a corresponding re
of fuell the ratio which must be maintained for verse manner.
1
the production of dry saturated isteam is always
The drum involves for the operating medium a
reestablished
after
a
disturbance
by
adjusting
59
the quantity of liquid fed into the boiler to a flow resistance of a certain magnitude. When
corresponding new value. Should the disturbance great quantities of steam are needed it may hap
of the ratio have been caused by a change in the Den that the resistance to ilow attains such a
high value that the steam generator is not able to
quantity of liquid fed into the boiler this dis
supply
the desired quantity of steam. Another
55 turbance will be eliminated, whereupon the
boiler will, consequently, supply again the same object of my invention is to provide an arrange 65
ment, whereby the above-mentioned drawback is
amount of steam which it has also supplied in the overcome.
This may be accomplished according
former state of equilibrium. If, however, the dis
the invention by arranging the drum in parallel
turbance has been caused by varying the supply to
relation with a regulable tubular part which
so of fuel it may be eliminated by causing the gov permits
a direct connection of the evaporatlng
erning apparatus to act upon the feed valve 26,
that is to sa?, not to en'ect a correction of the
supply of fuel. The result is that the delivery of
the boiler has varied as soon as the valve 26 has
65 been adjusted after the disturbance in such a
manner that the conduit it supplies again dry
saturated steam. If the demand of `steam has
not changed in the meantime a change in pres
sure occurs immediately at the point of the boiler
70 at which steam is drawn ofi' by the consumer.
Since the supply of fuel is controlled at 35-32
in accordance with the pressure of the steam sup
plied to theconsumer a correction of the supply
of fuel is brought about. Also in this case, as
75 will be apparent, the particular operating factor
l
portion with the superneaung portion.. The sum`
of the quantities of steam flowing through the
drum andthe parallel-connected pipe may be
then so adjusted that the consuming apparatus
always receives the desired quantity of steam
without the supply of steam from the boiler being
impaired in any way by the resistance of the
drum.
That particular feature oi' the invention is>
shown in. Fig. 2 in diagrammatic form. The
steam generator there indicated may be in its
other structural features similar to the one shown
in Fig. 1. The liquid operating medium is sup'
plled by a pump (not shown) to the economizer
l (see also Fig. l) which ’is located in the heat
2,118,559
convection zone of the boiler, and in which the
medium is preheated; From there it passes into
the tube section 1, which is located in the heat ra
diating zone and which is partly still used for pre~
heating the liquid. Only in the last portion of
section 1 the evaporation commences. From
there the medium flows into the principal evap
orator || which is located in the heat convection
zone. From this evaporator the then completely
10 vaporous medium flows through pipe |0| to the
control system to be described hereinafter. -The
-pipe H2 thence conducts the operating medium
to the superheater |1 and 2| to which the pipe
ofthe consuming apparatus is connected, and
15 which lies in the heat convection zone.
The pipe |0| connected behind the zone of
evaporation feeds steam into the coil |04 within
the drum |08 through the valve ||4 and the pipe
|03. The steam entering the coil |04 is dry
20 saturated as ‘well as the steam flowing from the
drum tothe pipe ||2 through the pipe |06. The
boiler is regulated according to the water level
|05 in the auxiliary drum |08 in the manner
shown in Fig. 1. It should be noted that by thev
25 term “drum” not the structural part of an ordi
nary drum boiler is to be understood but that
a structural part is involved which is rather to
be considered as an auxiliary element for es
tablishing an artificial water level.
30
In order to produce a suilicient quantity of
steam in the case of a great demand of steam
by the consuming apparatus the pipe |0| is con
nected to the pipe || 2 through the pipe |01, i~ e.,
a direct connection between the evaporator ||
and superheater I1 is established in parallel re
3
vailing operating conditions of the boiler. also
-the drum |08 receives 'superheated steam which
partly evaporates the liquid content of the drum.
'I'his must "be taken into yconsideration when
regulating the boiler. `
I claim as my lnvention:_`
`
,
1. In a steam generator of the forced single
flow tubular type having means for normally
supplying amounts of operating and heating me
dium per unit of time at a ratiocommensurate 10
with the normal steam consumption per time
unit, a liquid storage container interposed into
the flow circuit and restricted toexclusively re
ceive operating medium directly from and vdis
charge it exclusively into said circuit, and being 15.
partly filled with liquid operating medium` to a
desired normal level, means for normally sup
plying dry saturated steam through said liquid
into the top of said container whereby neither
evaporation by superheated steam nor increase 20
of said liquid through condensation of wet steam
occurs during normal operation, means for super
heating the steamv discharged from said con
tainer, and means responsive to the variation of
the normal liquid level in saidcontainer, due to
the supply of Vsuperheated or wet steam in case
of under or overload respectively, for varying the '
"normal ratio of operating liquid and fuel supply
to reestablish the normal liquid level in said
container.
2. In a steam generator of the forced single flow
tubular type having means for normally sup
plying amounts of operating and heating me
dium. per unit of time at a ratio commensurate'
with the normal steam consumption per time
lation to the drum |08. The connection itseli unit, a liquid storage container interposed into
is regulable by a valve ||| which is adjusted by ,the iiow circuit and restricted to exclusively re
hand or as hereinafter described automatically. . ceive operating medium directly from and dis
If the drop in pressure Ap in the drum |08 is charge it into said circuit, and being partly filled
40 so great as not to permit the passage of sum
with liquid operating medium to a desired normal
cient steam therethrough the valve | I I is opened level, means for normally supplying dry satu
to such an extent that the remaining part of rated steam to said liquid whereby neither evap
steam may pass through pipe ||2 directly to the oration nor increase of said liquid through con
superheater through the parallel-connected pipe densation occurs during normal operation, means
45
|01. 'I'he total quantity of steam flowing to the
superheater consists, consequently, of two quan
tities which flow in parallel relation with each
other into the pipe ||2 through the drum |08
and the pipe |01. For automatically control
ling the valve |||, for instance a pressure differ
ential responsive piston device | I5 may be em
ployed which is influenced, on the one hand, by
the pressure prevailing in the pipe |06 and effec
tive at the point ||0 from which the impulse
is transmitted to one side of the piston of device
||5 and, on the other hand, by the pressure
prevailing in the conduit |03 and effective at
the point |09 from which the impulse ls trans
mitted to the other side of the piston of device
60 ||5. With a given quantity of steam consump
tion the valve ||| begins, therefore, to open and
moves more and more toward the open position
the more the steam demand increases.`
If the operating conditions of the boiler should
cause the steam issuing from the pipe |0| to
become wet, the moisture might under certain
circumstances reach the superheater, which may
as is well known give rise to trouble and cause
a deposit of sedimentary salts. It is, therefore,
preferable to insert a water separator |02 at the
junction of pipes |0| and |01. Thewater col
4lecting in this separator is then forced into the
drum |08.
If, however, the steam ñowing through the
75 pipe |0| is already superheated owing to the pre
for superheating the steam discharged from said
container, and means _responsive to the variation
of the normal liquid level in said container, due
to the supply of superheated or wet steam in ,
case of under or overload respectively, for vary
ing the amount of operating liquid supply to the 50
generator and means for controlling the fuel
supply inversely to the pressure of theA steam '
delivered from the generator, for varying the
normal ratio of operating liquid and fuel supply
in accordance> with the newly prevailing operaia
ing conditions and to reestablish the normal liq-uid level in said container.
3. In a steam generator of the -forced single »
flow tubular type having means for normally
supplying amounts of operating and heating nie
dium per unit of time at a ratio commensurate
with the normal steam consumption per time unit,
a liquid storage container interposed into the
flow circuit and restricted to exclusively receive
operating medium directly from and discharge it 65
into said circuit, and being partly ñlled with liq
uid operating medium to a desired normal level,
means for normally supplying dry saturated
steam to said liquid whereby neither evaporation
nor increase of said liquid through condensation 70
occurs during normal operation, means for super
heating the ster-.m discharged from said container,
means responsive to the quantity of steam issuing
from said container and means responsive to the
variation of the normal liquid level in said con 75
4
9,118,559
tainer, due to the supply of superheated or wet
lsteam in case ci under or overload respectively,
for varying the normal ratio of operating liquid
and fuel supply to reestablish the normal liquid
level in said container.
» 4. In a steam generator of the forced single
iiow tubular type _having means for normally
supplying amounts of operating and heating me
dium per unit oi' time at a ratio commensurate
10 with the normal steam consumption per time unit,
~ a liquid storage container interposedv into the
ilow circuit _and restricted tol exclusively receive
operating medium directly from and discharge
it into said circuit, and being partly illled with
15 liquid operating medium to a desired normal
level, means for normally supplying dry saturated
steam to said liquid whereby neither evaporation
nor increase of said liquid through condensation
occurs during normal operation, means for super
.20 heating the steam discharged from said con
tainer, and means responsive to the variation of
the normal liquid level in said container, due to
the supply of superheated or wet steam in case
of under or overload respectively, for varying the
25 normal ratio of operating liquid and fuel supply
`to reestablish the normal liquid level in said con
tainer and a steam by-pass between the steam
input and output side of said container and means
for controlling the amount ofsaid by-pass.
5. In a steam generator of the forced single
iiow tubular type having means for normally sup
plying-amounts of operating and heating me
dium per unit of time at a ratio commensurate
with the normal steam consumption per time
unit, a liquid storage container interposed into
the flow circuit and restricted to exclusively re
ceiveoperating medium directly `from and dis
charge it into said circuit, and being partly
filled with liquid operating medium to a desired 10
normal level, means for normally supplying dry
saturated steam to said liquid whereby neither
evaporation nor increase of said liquid through
condensation occurs during normal operation,
means for superheating the steam discharged 15
from said container, and means responsive to the
variation oi' the normal liquid level in said con
tainer, due to the supply of superheate'd or wet
steam in case of under or overload respectively,
for varying the normal ratio of operating liquid 20
and_fuel supply to reestablish the normal liquid
level in said container, and a steam by-pass be
tween the steam input and output side of said
container and means responsive to the pressure
difference between said two sides for controlling 25
the amount of said steam by-pass.
A
WILHELM ABENDROTH.
Документ
Категория
Без категории
Просмотров
0
Размер файла
699 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа